MOCVD processes for producing III-V films on various substrates are well known and well documented in the literature. A few references to this subject, all disclosures of which are incorporated herein by reference, include:
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To obtain optimum MOCVD coatings a number of factors have been considered, such as substrate surface condition or treatment, deposition rate, occurrence of side reactions, physical state of the metal organic, pyrolysis temperature, and the like. On the basis of these and other various factors, arsine (AsH.sub.3) and trimethylarsine (Me.sub.3 As) have been used in recent years as the arsenic source materials. However in order to obtain the desired purity and quality of MOCVD-grown materials, it has been found necessary to carefully regulate AsH.sub.3 over pressure as well other operating conditions.